Am replacing a drain pipe under a concrete garage floor. Jackahmmering a trench to accomodate a 4" wide pipe. Backfilling and tamping down prior to pouring the concrete patch. With a jagged cut from the jackhammer, will the patch be suffice with wire mesh only? The trench is no wider than 10 inches or so.

Bondo

05-28-2010 06:19 AM

Quote:

will the patch be suffice with wire mesh only?

Yes...

stadry

05-28-2010 07:12 AM

you won't need mesh however IF you use it, be certain its centered vertically midpoint +/- 5% which's .2" - i wouldn't use it & don't in 4" slabs,,, its usually not recommended on 4" slabs.

you probably WILL have to score jnts every 15" across the patch OR await while the conc to cracks on its own,,, you probably know to wet the sides of the existing conc so its dryness won't suck out the new conc's moisture

cougar01

05-28-2010 07:49 AM

Thanks for the replies! I guess my main concern was if it would crack over time with the car running over it (pulling in and out of garage)

stadry

05-28-2010 09:13 AM

YES, IT will CRACK,,, since conc likes to be square, we place contraction jnts in it so it'll crk where WE want it to crk.

imagine your patch's a conc highway,,, those joints're placed at EXACT locations for a reason,,, that was our work for yrs - putting specific ' thump-thump ' in conc hgwys to prevent random cracking :laughing: